U.S. patent number 4,269,172 [Application Number 05/848,458] was granted by the patent office on 1981-05-26 for solar water-heating apparatus.
Invention is credited to Peter D. Parker, Lawrence J. Walton, Robert N. Walton.
United States Patent |
4,269,172 |
Parker , et al. |
May 26, 1981 |
**Please see images for:
( Certificate of Correction ) ** |
Solar water-heating apparatus
Abstract
A solar hot-water system having an absorber formed of plastic
ducting adapted to be arranged unobtrusively on a roof surface
whereby the water is heated by means of direct radiation from the
sun and by means of conduction from the roof surface on which the
ducting is supported.
Inventors: |
Parker; Peter D. (Miami Keys,
Queensland, AU), Walton; Robert N. (Miami Keys,
Queensland, AU), Walton; Lawrence J. (Miami Keys,
Queensland, AU) |
Family
ID: |
25642142 |
Appl.
No.: |
05/848,458 |
Filed: |
November 4, 1977 |
Foreign Application Priority Data
|
|
|
|
|
Nov 8, 1976 [AU] |
|
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PC8037 |
Feb 4, 1977 [AU] |
|
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PC8945 |
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Current U.S.
Class: |
126/621; 126/622;
126/663; 165/56; 165/169; 126/660; 126/906; 165/76; 165/171 |
Current CPC
Class: |
F24S
10/73 (20180501); F24S 20/67 (20180501); F24S
10/753 (20180501); F24S 80/30 (20180501); Y02B
10/20 (20130101); Y02E 10/44 (20130101); Y10S
126/906 (20130101) |
Current International
Class: |
F24J
2/46 (20060101); F24J 2/24 (20060101); F24J
2/00 (20060101); F24J 2/04 (20060101); F24J
2/26 (20060101); F24J 003/02 () |
Field of
Search: |
;126/270,271,432,446-450,DIG.2 ;237/1A
;165/168,169,171,56,172,173,76,176,46,48,49
;29/157R,157.3R,157.3A |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Yeung; James C.
Attorney, Agent or Firm: DeLio and Montgomery
Claims
I claim:
1. Solar water-heating apparatus including
a header having an inlet for water to be heated,
a duct assembly,
a manifold arranged to communicate with said header through said
duct assembly,
a hot water discharge outlet from said manifold,
said duct assembly having a plurality of spaced-apart ducting
members each being adapted to communicate with, for through-flow
between, said header and said manifold through a respective one of
a plurality of spaced-apart, plug-in connections provided along
said header and said manifold, said ducting being a resilient
plastic extrusion member of indefinite length and having a
plurality of substantially identical passageways extending
longitudinally therethrough and disposed in spaced side-by-side
relationship, and
a roof sheet for supporting said ducting, said roof sheet having a
rectantular body portion, upstanding complementary side engagement
portions,
said body portion extending between said upstanding complementary
side engagement portions whereby said sheet may be connected in
operative edge-to-edge overlapping relationship with a similar
sheet at each side thereof and said rectangular body portion
including a re-entrant recess extending parallel to said engagement
portions and arranged to closely accommodate therein said resilient
ducting whereby the latter may be operatively retained in said
recess by forcing said ducting through the entrance of and into
said re-entrant recess.
2. Solar water-heating apparatus including
a header having an inlet for water to be heated,
a duct assembly adapted to be supported directly on a sun-exposed
supporting surface,
a manifold arranged to communicate with said header through said
duct assembly,
a hot water discharge outlet from said manifold,
said duct assembly having a plurality of spaced-apart ducting
members each being adapted to communicate with, for through-flow
between, said header and said manifold through a respective one of
a plurality of spaced-apart, plug-in connections provided along
said header and said manifold,
said header and said manifold being of elongated tubular form and
adpated to be disposed in side-by-side relationship across said
supporting surface and include a plurality of spaced apertures for
said plug-in connections and each said ducting comprises an
elongate plastic extrusion member including a pair of enclosed
passageways extending therethrough, one said passageway being
adapted to communicate at one end through said plug-in connection
with said header and the other said passageway being adapted to
communicate at its corresponding end through said plug-in
connection with said manifold and there being provided transfer
means cooperating with said ducting remote from said header and
said manifold for transferring water from said one pasageway to
said other passageway,
said transfer means comprising a hollow body having a pair of
tubular inlet-cum-outlet spigots each being adapted to be forced
into sealing plug-in engagement with the bore of a respective one
said passage-way for transferring water from the said one
passageway to said other passageway, and wherein each said plug-in
connection between said ducting and said header or said manifold is
made by means of a tubular adaptor adapted to be forced into
sealing engagement at one end with the bore of said passageway and
at its other end into sealing engagement with the respective said
aperture, and
said supporting surface being a roof formed of a plurality of edge
overlapping sheets each having a rectangular body portion extending
between upstanding complementary side engagement portions whereby
said sheet may be connected in operative edge-to-edge overlapping
relationship with a similaar sheet at each side thereof and said
rectangular body portion including a re-entrant recess extending
parallel to said side engagement portions and arranged to closely
accommodate therein said resilient ducting whereby the latter may
be operatively retained in said recess by forcing said ducting
through the entrance of and into said re-entrant recess.
3. Solar water-heating apparatus according to claim 2, wherein
there is provided a solid transparent panel spaced above said
rectangular body portion so as to prevent heat loss by convection
from said ducting supported beneath said panel, the latter being
supported edgewise along said complementary side engagement
portions.
4. Solar water-heating apparatus according to claim 3, wherein
there are provided supporting clips adapted to be engaged over each
said upstanding portion of said roof sheet to provide at each side
thereof a recess adapted to operatively engage the edge of said
panel to support same.
5. Solar water heating apparatus of the type including an inlet
manifold and an outlet manifold and an absorber assembly supported
on an exposed roof and being constituted by a plurality of elongate
flexible plastic ducting members having a passageway therethrough
through which fluid may flow from said inlet manifold to said
outlet manifold; characterized in that said exposed roof comprises
a roof having a plurality of contintuous spaced-apart recesses
extending thereacross and in that each said flexible ducting member
is supported directly on said exposed roof and is constrained
within a respective said recess.
6. Solar water heating apparatus according to claim 5, wherein each
said passageway is connected to the respective said inlet manifold
or outlet manifold by means of a push-in connector having a pair of
spigot connector ends, a respective one of which is adapted to be
forced into sealable engagement with said passageway and the other
said spigot end being adapted to be forced into sealable engagement
with an aperture formed in the respective said inlet manifold or
said outlet manifold.
7. Solar water heating apparatus according to claim 5 wherein said
roof is a metal roof including a plurality of roof sheets each
having a rectangular body portion, each said rectangular body
portion including a said recess, each said recess being constituted
by a re-entrance recess extending longitudinally of said sheet and
arranged to closely accommodate
therein a respective said ducting member whereby the latter may be
operatively constrained with said recess by forcing said ducting
member through the entrance of and into the said re-entrance
recess.
8. Solar water heating apparatus according to claim 5 wherein said
roof is a tile roof comprising a plurality of overlapping tiles
each having a depression extending thereacross which is adapted to
be aligned with complementary depressions of the adjacent tiles so
as to form a respective said recess extending across said roof and
wherein said ducting members are constrained in respective said
recesses by clip means adapted to be engaged with said tiles above
said ducting members to secure said ducting members in said
recesses.
9. Solar water heating apparatus including a header having
an inlet for water to be heated, a duct assembly adapted to be
supported directly on a roof or other sun-exposed supporting
surface,
a manifold arranged to communicate with said header through said
duct assembly,
a hot water discharge outlet from said manifold, said duct assembly
having a plurality of spaced-apart ducting members each being
adapted to communicate with, for through-flow between, said header
and said manifold through a respective one of a plurality of spaced
apart, push-fit plug-in connections provided along said header and
said manifold,
said header and said manifold being of elongated tubular form and
adapted to be disposed in side-by-side relationship across said
supporting surface and include a plurality of spaced apertures for
said plug-in connections and each said ducting member comprises an
elongate plastic extrusion member including a pair of enclosed
passageways extending therethrough, one said passageway being
adapted to communicate at one end through said plug-in connection
with said header and the other said passageway being adapted to
communicate at its corresponding end through said plug-in
connection with said manifold and there being provided transfer
means co-operating with said ducting member remote from said header
and said manifold for transferring water from said passageway to
said other passageway,
said transfer means comprising a hollow body having a pair of
tubular inlet-cum-outlet spigots each being adapted to be forced
into sealing plug-in engagement with the bore of a respective one
said passageway for transferring water from the said one passageway
to said other passageway, and wherein each said plug-in connection
between said ducting and said header or said manifold is made by
means of a tubular adaptor adapted to be forced into sealing
engagement at one end with the bore of said passageway and at its
other end into sealing engagement with the respective said
aperture.
10. Solar water heating apparatus including an inlet manifold, an
outlet manifold and an absorber assembly through which fluid may
pass from said inlet manifold to said outlet manifold and said
absorber assembly being constituted by a plurality of elongate
flexible ducting members supported directly on a metal roof, said
metal roof comprising a plurality of roof sheets each having a
rectangular body portion extending between upstanding complimentary
side engagement portions whereby each said sheet may be connected
in operative edge to edge overlapping relationship with a similar
sheet at each side thereof and said rectangular body portion
including a recess extending parallel to said side engagement
portions for locating said flexible ducting members, each said
ducting member having at least a pair of passageways extending
longitudinally therethrough whereby each passageway of the
respective ducting members may be operatively connected at its end
adjacent said manifolds to a respective one of said inlet manifold
or said outlet manifold by means of a push-in connector having a
pair of spigot connector ends adapted to be forced into sealable
engagement with said passageway and an aperture formed in said
inlet manifold or said outlet manifold and there being provided a
transfer duct assembly for each said ducting member, said transfer
duct assembly having a pair of push-in spigot connector ends each
adapted to be forced into sealable engagement with a respective one
said passageway at the end of said ducting member remote from said
manifolds to interconnect said passageways whereby liquid may flow
from said inlet manifold through one said passageway for return to
said outlet manifold through the other said passageway of each said
ducting member.
11. Solar water-heating apparatus according to claim 10, wherein
said inlet manifold and said outlet manifold are flexible pipe
formed of plastics material whereby the apertures therein for said
spigot connectors may be formed on site and wherein said spigot
connectors are formed of plastics material.
12. Solar water-heating apparatus according to claim 11, wherein
each said ducting member includes four substantially identical and
spaced apart passageways each passageway having a circular
cross-sectional configuration and being formed within a respective
tubular housing portion and there being provided continuous
connecting webs extending along said ducting member and between
adjacent tubular housing portions.
13. Solar water-heating apparatus according to claim 10, wherein
the width of said recess is substantially equal to the overall
width of said ducting members.
14. Solar water-heating apparatus according to claim 10, wherein
there is provided a light transmitting panel spaced above said body
portion so as to prevent heat loss by convection from said ducting
member supported beneath said panel, the latter being supported
edgewise along said complimentary side engagement portions.
15. Solar water-heating apparatus according to claim 14, wherein
there are provided supporting clips adapted to be engaged over each
said upstanding portion of said roof sheet to provide at each side
thereof a recess adapted to operatively engage the edge of said
panel to support same.
16. Solar water heating apparatus including an inlet manifold, an
outlet manifold and an absorber assembly through which fluid may
pass from said inlet manifold to said outlet manifold and said
absorber assembly being constituted by a plurality of elongate
flexible ducting members supported directly in spaced side by side
relationship on a tile roof and each being located in respective
aligned recesses formed in overlapping tiles, and there being
provided clip means adapted to be engaged between the sides of the
respective tile recesses above said ducting members to secure said
ducting members in said recesses and each said ducting member
having at least a pair of passageways extending longitudinally
therethrough whereby each passageway of the respective ducting
members may be operatively connected at its end adjacent said
manifolds to a respective one of said inlet manifold or said outlet
manifold by means of a push-in connector having a pair of spigot
connector ends adapted to be forced into sealable engagement with
said passageway and an aperture formed in said inlet manifold or
said outlet manifold and there being provided a transfer duct
assembly for each said ducting member, said transfer duct assembly
having a pair of push-in spigot connector ends each adapted to be
forced into sealable engagement with a respective one said
passageway at the end of said ducting member remote from said
manifolds to interconnect said passageways whereby liquid may flow
from said inlet manifold through one said passageway for return to
said outlet manifold through the other said passageway of each said
ducting member.
17. Solar water heating apparatus according to claim 16, wherein
said inlet manifold and said outlet manifold are flexible pipe
formed of plastics material whereby the apertures therein for said
spigot connectors may be formed on site and wherein said spigot
connectors are formed of plastics material.
18. Solar water heating apparatus according to claim 17, wherein
each said ducting member includes four substantially identical and
spaced apart passageways each passageway having a circular
cross-sectional configuration and being formed within a respective
tubular housing portion and there being provided continuous
connecting webs extending along said ducting member and between
adjacent tubular housing portions.
19. Solar water heating apparatus including juxtapositioned inlet
manifold and outlet manifold and an absorber assembly through which
fluid may pass from said inlet manifold to said outlet manifold and
said absorber assembly being constituted by a plurality of elongate
flexible plastic ducting members supported directly on a metal
roof, said metal roof being formed from a plurality of metal sheets
each having a rectangular body portion extending between upstanding
complementary side engagement portions whereby each said sheet may
be connected in operative edge-to-edge overlapping relationship
with a similar sheet at each side thereof and wherein said
rectangular body portion of each said sheet is provided with a
recess which extends along said sheet parallel to said side
engagement portions, each said recess being adapted to nestingly
receive a respective said ducting member and having a width
substantially equal to the overall width of said ducting member,
and each said ducting member having at least a pair of passageways
extending longitudinally therethrough whereby each passageway of
each respective ducting member may be operatively connected at one
end of said ducting member to a respective one of said inlet
manifold or said outlet manifold and there being provided a
transfer duct assembly for each ducting member to interconnect said
passageways at their other end whereby liquid may flow from said
inlet manifold through one said passageway for return to said
outlet manifold through the other said passageway.
20. Solar water heating apparatus according to claim 19, wherein
each said ducting member includes a plurality of substantially
identical and spaced-apart passageways each passageway having a
circular cross-sectional configuration and being formed within a
respective tubular housing portion and there being provided
continuous connecting webs extending along said ducting member and
between adjacent tubular housing portions.
21. Solar water heating apparatus according to claim 20, wherein
said recess diverges from its open face the width of which is
slightlyless than the overall width of said ducting member so as to
provide a restricted opening to said recess, said restricted
opening constituting said constraint.
22. Solar water heating apparatus according to claim 19, wherein
there is provided a light transmitting panel spaced above said body
portion so as to prevent heat loss by convection from said ducting
member supported beneath said panel, the latter being supported
edge wise along said complementary side engagement portions.
23. Solar water heating apparatus according to claim 22, wherein
there are provided supporting clips adapted to be engaged over each
said upstanding side portion of said roof sheet to provide at each
side thereof a recess adapted to operatively engage the edge of
said panel to support same.
24. A metal roofing sheet for the solar water heating apparatus as
defined in claim 19, said metal roofing sheet having a rectangular
body portion extending between upstanding complementary side
engagement portions whereby said sheet may be connected in
operative edge-to-edge overlapping relationship with a similar
sheet at each side thereof and said rectangular body portion
including a recess extending parallel to said side engagement
portion and arranged to closely accommodate therein said ducting
member.
25. A metal roofing sheet according to claim 24, wherein the width
of the open face of said recess is slightly less than the overall
width of said ducting member and said recess diverges inwardly,
said restricted open face of said recess constituting said
constraint.
26. Solar water heating apparatus including juxtapositioned inlet
manifold and outlet manifold and an absorber assembly through which
fluid may pass from said inlet manifold to said outlet manifold and
said absorber assembly being constituted by a plurality of elongate
flexible plastic ducting members supported directly on a tile roof
said tile roof comprising a plurality of overlapping tiles each
having a pair of depressions extending thereacross which are
adapted to align with complementary depressions of the adjacent
tiles so as to form recesses extending across the roof and wherein
said ducting members are constrained in the respective said
recesses by means of a clip fixed to said tiles and being adapted
to overlie said ducting member adjacent the overlap of the
respective tiles, each said ducting member having at least a pair
of passageways extending longitudinally therethrough whereby each
passageway of each respective ducting member may be operatively
connected at one end of said ducting member to a respective one of
said inlet manifold or said outlet manifold and there being
provided a transfer duct assembly for each said ducting member to
interconnect said passageways at their other end whereby liquid may
flow from said inlet manifold through one said passageway for
return to said outlet manifold through the other said passageway.
Description
This invention relates to a method of and apparatus for heating
water.
At present there are many solar water-heating assemblies available
which operate efficiently to provide hot water for domestic
purposes or at a lower temperature for say swimming pool heating or
space heating. A major disadvantage of the presently available
apparatus is their cost, mainly because of the copper and stainless
steel content in their construction, together with the unsightly
appearance of the installation. Such installations commonly
comprise a conspicuous device placed on a visible portion of a
supporting roof and having a shape which does not blend with the
surroundings. Solar heating installations are particularly
unsightly when one absorber is positioned on the roof for supplying
the domestic hot water and another absorber is positioned on the
roof for supplying the lower temperature hot water for say pool
heating or space heating.
An object of the present invention is to provide hot water heating
apparatus which will overcome the abovementioned disadvantages and
which will be reliable and efficient in use. Other objects and
advantages of the invention will hereinafter become apparent.
With the foregoing and other objects in view, this invention
resides broadly in solar water-heating apparatus including a header
having a inlet for water to be heated; a manifold arranged to
communicate with said header through a flexible duct assembly
adapted to be supported directly on a roof or other sun-exposed
supporting surface, and a hot water discharge outlet from said
manifold.
The present invention also resides in the provision of ducting
members for solar water-heating purposes and comprising a resilient
plastic extrusion member of indefinite length and having a
plurality of substantially identical passageways extending
longitudinally therethrough and disposed in spaced side by side
relationship.
In addition, the present invention includes a roof sheet for
supporting such ducting members and comprising a rectangular body
portion extending between upstanding complementary side engagement
portions whereby said sheet may be connected in operative edge to
edge overlapping relationship with a similar sheet at each side
thereof and said rectangular body portion including a re-entrant
recess extending parallel to said side engagement portions and
arranged to closely accommodate therein said resilient ducting
member whereby the latter may be operatively retained in said
recess by forcing said ducting member through the entrance of, and
into, said re-entrant recess.
In order that the invention may be more readily understood and put
into practical effect, reference will now be made to the
accompanying drawings which illustrate the invention and
wherein:
FIG. 1 illustrates generally a typical solar water-heeating
installation according to the present invention;
FIG. 2 is a cut-away perspective view of portion of the roof
section shown in FIG. 1;
FIG. 3 is a perspective view of a preferred form of the ducting
according to the present iinvention;
FIG. 4 is a cut-away perspective view showing the ducting supported
operatively in the re-entrant recesses of a roof sheet;
FIG. 5 is an end view showing the connection of a glazing panel to
the roof sheet;
FIG. 6 is a perspective view of the tubular adaptor for connecting
the passageways of the ducting to the inlet header and the outlet
manifold;
FIG. 7 is a perspective view of a pair of roof tiles shown in
operative relationship with the ducting of the present invention
fixed thereto;
FIG. 8 is a perspective view of an alternate form of tile for use
with the invention;
FIG. 9 is a diagrammatic perspective view illustrating the
installation of a further embodiment of the invention;
FIG. 10 is a perspective view of portion of an alternate form of
ducting made in accordance with the invention;
FIG. 11 illstrates a return adaptor for use with the ducting
illustrated in FIG. 10;
FIG. 12 is a control valve adaptor for use with the ducting
illustrated in FIG. 10; and
FIG. 13 illustrates a connector engageable with the ducting
illustrated in FIG. 10 for securing same to a roof structure.
In a typical pool installation, re-circulated water is pumped from
the pool and returned via a filtration plant. In the present
invention, the pumped pool water is directed, prior to passage
through the filtration plant, to the heating apparatus and then
back through the filtration plant to the pool. The heating
apparatus includes a header disposed in or adjacent the guttering
of the roof, or at the peak of the roof as desired, and is provided
with a plurality of outlet apertures each of which is adapted to
communicate with a respective passageway of one of a plurality of
spaced elongate ducting members which extend away from the header
in an exposed position across and in close contact with the roof
for passage of water from the header to an outlet manifold
connected in similar manner whereby the water pumped through said
ducting absorbs solar heat by direct radiation as well as by
conduction from the roof surface which acts as a large heat
collector. This feature ensures that efficient use is made of the
available space without overly detracting from the original
appearance of the roof. Furthermore the ducting may be formed from
say extruded P.V.C. material or the like, so that the installation
costs may be minimised. The present invention, according to one
aspect, provides a high temperature solar water-heating apparatus
10 and a low temperature solar water-heating apparatus 11 both of
which may be supported on and incorporated into an exposed roof 12
in such manner that their application to the roof does not overly
distract from the appearance of the roof 12. In order to achieve
this, the properties of both plastic and metal are combined by
providing a metal roofing sheet 13 of the type having a rectangular
body portion 14 extending between upstanding complementary side
engagement portions 15 and 16 in known manner but which varies from
the standard sheet by the provision of re-entrant recesses 17
formed in the body portion 14 adapted to closely accommodate
plastic water ducting 18 therein. As the ducting 18 is of a
resilient nature being formed of say P.V.C. or similar material, it
may be sprung into the recess 17 by forcing it past the restricted
entrance thereto into the diverging recess and the width dimension
of the recess 17 is less than the overall width of the ducting 18
so that when the ducting is operatively engaged in the recess 17,
it will be held against displacement from its operative
position.
In this embodiment, the ducting 18 extends down the roof surface
and includes four circular cross-section passageways 19, two of
which are adapted to communicate at their upper end with an inlet
header 20 while the other two are adapted to communicate at their
corresponding upper ends with the outlet manifold 21. Transfer
means 22 are provided at the lower ends of the ducting 18 to
transfer the water from the passageways communicating with the
inlet header 20 to the pasageways communicating with the outlet
manifold 21. As shown, the transfer means comprise U shaped round
tubes which are so dimensioned as to be a tight plug-in fit into
the passageways 19. The plug-in connection may be formed with a
plastic solvent glue or the like to weld the transfer means to the
ducting to prevent leakage.
The upper plug-in connections 23 made between the passageways 19
and the inlet header 20 or the outlet manifold 21 are formed by
means of a tubular adaptor 24 as shown in FIG. 6 which has an
intermediate abutment flange 25 separating an enlarged ribbed end
26, adapted for sealing plug-in connection with the respective
passageway, and a smaller diameter spigot end 27 adapted for
plug-in connection to the respective aperture formed in their inlet
header 20 or outlet manifold 21. Preferably the ducting is made of
P.V.C. as is the transfer means 22, the adaptor 24 and the inlet
header 20 and the outlet manifold 21. If necessary, solvent glue
can be used to seal the connection between the adaptor 27 and the
header 20 or manifold 21 which may be supported out of sight
beneath the ridge cap 28 of the roof 12.
The heating apparatus illustrated in FIG. 2 is adequate for low
temperature heating purposes such as for heating pools or for space
heating and for this purpose, water is supplied to the inlet header
20 from the pool pumping plant via piping 29 and is returned from
the outlet manifold via the piping 30. However, such an
installation is not adequate for supplying normal domestic hot
water mainly due to the heat losses from the ducting 18 by
convection preventing the necessary high temperature being
attained. Accordingly, for domestic hot water heating purposes
there is additionally provided a transparent cover panel 31 adapted
to be supported spaced above the ducting 18 by means of supporting
clips 32 which engage over the upstanding side engagement portions
33a and 33b and have outwardly directed channels 34 for engagement
with the longitudinal edges 35 of the panels 31. The panel
minimises heat loss from the ducting 18 so that the temperature of
the water therein may be elevated to the desired temperature. In
order that the ducting 18 may withstand the additional temperatures
and/or pressures, it may be formed in a stronger version having say
greater thickness dimensions, or say formed of a different
material, more suited to the particular application. Of course,
during installation the ducting 18 may be cut to any desired length
and the webs portions 36 between the respective passageways 19 may
be slit to enable the respective passageways which engage the inlet
header and the outlet manifold to be cut to length to suit the
location of the inlet header and the outlet manifold and bent
upwards to facilitate plug-in connection therewith, as clearly
shown in FIG. 2.
A feature of the present invention is that the ducting 18 nests in
close contact with the roof surface so that heat is absorbed
directly from the sun and indirectly from the roof which forms a
large heat sink to collect the enrgy from the sun for transference
to the ducting 18. This indirect heating is enhanced by the close
fit of the ducting 18 within the recess 17 which provide areas for
heat transference along the bottom face of the ducting 18 and also
along the side faces of the outer pair of passageways 19.
Preferably the ducting 18 is formed of black P.V.C. material or
other material coloured to blend with the colour of the
roofing.
The heating apparatus of the invention may be incorporated on a
tiled roof and for this purpose the present invention provides
roofing tiles 40 adapted to enable the ducting 18 to be secured in
the recesses 41 formed in the tiles. In one form, the tile 40 is
provided with a plurality of transversely aligned indents 42 at one
end and indents 45 at the opposite end and along the opposite
upstanding faces 43 at each side of the receses 41 and into any one
transversely aligned pair of which a flexible pin 46 may be
inserted above the ducting 18 to retain it in the recess 41. As
shown, this arrangement enables the ducting 18 to be clamped at
either side of the step from one tile to the next so that it is
maintained in close contact with the tile for good appearance and
to achieve maximum heat absorption from the tiles. An alternate
form of roofing tile is illustrated in FIG. 8 in which a bendable U
shaped tab 47 is fixed into the end of the tile and which may be
bent in use to bear down against the top surface of the ducting 18
to maintain it in position.
In the embodiment illustrated in FIGS. 9 to 13, the arrangement is
similar except that the ducting 18b includes three semi-circular
passageways 19b extending between perforated edge portions 48. The
perforated edge portions 48 are adapted to be engaged in headed
spigots 49 of a retention clip 50 which has a flat portion which
may be engaged between the joint between tiles or roof panels to
secure the ducting 18b to the roof. Furthermore, the transfer means
includes a two-into-one adaptor 51 as shown in FIG. 11 and the
plug-in connectors 52 for forming the connection between the
ducting 18b and the inlet header 20a and the outlet manifold 21a
includes a two-into-one adaptor together with a regulating valve 53
on the straight-through passage 19c. In this embodiment the header
and the outlet manifold are supported out of sight in the roof
gutter.
Of course it will be realised that the above has been given by way
of illustrative example only, and all such modifications and
variations as would be apparent to persons skilled in the art are
deemed to fall within the broad scope and ambit of the invention as
is defined in the appended claims.
* * * * *